Technical Field
The present disclosure relates to a negative electrode material of a lithium battery and a method for manufacturing the same. More particularly, the present disclosure relates to a negative electrode material of a lithium battery that contains silicon carbide and multi-layer graphene and a method for manufacturing the same.
Description of Related Art
Secondary batteries are widely used in recent days. Secondary batteries have advantages of rechargeability, light weight and high operation voltage, thereby solving the problems of relatively low operation life and low capacity, and bring convenience to the use of electronic devices as well as give consideration to both environment and economy.
The operation principle of secondary batteries is based on the oxidation-reduction reaction in the field of electrochemistry. The basic structure of an electrochemistry battery includes a positive electrode, a negative electrode, an isolation film located between the positive electrode and the negative electrode, and an electrolyte used for the reaction. FIG. 1 shows a basic structure of a conventional lithium battery 100 in which a cylinder shaped lithium battery 100 is demonstrated. The lithium battery 100 includes a positive electrode 101, a negative electrode 102 and an isolation film 103. The electrolyte is filled between the positive electrode 101 and the negative electrode 102. The isolation film 103 is used to avoid short circuit caused by contact of the positive electrode 101 with the negative electrode 102.
When the lithium battery 100 is in a discharge state, a reduction reaction involving the gain of electrons is occurred on the positive electrode 101 while an oxidation reaction involving the loss of electrons is occurred on the negative electrode 102. Opposite reactions are occurred when the lithium battery 100 is in a charge state.
So-called lithium battery is referred to as an electrochemistry battery using lithium metal as a negative electrode active material. The lithium battery has advantages of high activity, high electromotive force and light weight. However, the manufacturing cost of the lithium battery using lithium metal as a negative electrode active material is still too high. Moreover, during charge-discharge cycles, the lithium ion will be deposited and dissolved repeatedly on the surface of the lithium metal and a dendritic structure is then formed. When the dendritic structure is gradually accumulated, the isolation film will be pierced through, and the dendritic structure will contact with the positive electrode thereby forming a short circuit. Moreover, large amount of reaction heat will be released, thus the lithium battery will fail or explode.
To solve the problems of low effectiveness, insecurity usage and high cost when using the lithium metal as the negative electrode active material of the lithium battery, non-metal compound such as carbon or carbon composite has been proposed to replace the lithium metal. However, the lithium battery made from such non-metal compound still has disadvantages of low effectiveness and low lifetime. Furthermore, the manufacturing method for such kind of lithium battery is still too complicated and not cost-effective.
Therefore, there is a need to develop a new kind of negative electrode material of the lithium battery and its manufacturing method to increase the effectiveness and the usage life time.